This indicates that an attempt to exploit a Cross Site Scripting vulnerability in the Apache Web Server.
The Apache web server is vulnerable to a Cross Site Scripting attack because it does not properly sanitize malicious HTML code when displaying SSI error pages. This could lead to the execution of arbitrary HTML and web scripts.
Apache 2.0 before 2.0.43
Apache 1.3.0 up to 1.3.26
System Compromise: Remote attackers can gain control of vulnerable systems
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